Mobile load handling means, particularly tower cranes

ABSTRACT

A mobile tower crane with a tiltable, non-rotatable tower mounted on a mobile platform such as a truck, trailer or semitrailer vehicle. The mobile platform has raised side members which are effective to reinforce the platform against bending along its length, and also carry raised pivot means for the tower at the rear end of the vehicle, the pivot means co-inciding with the side of the tower which is uppermost when the tower is in the horizontal travelling condition.

United States Patent [191 Wellman Dec. 24, 1974 MOBILE LOAD HANDLING MEANS,

PARTICULARLY TOWER CRANES [75] Inventor: Donald Edward Wellman, Komoka,

Ontario, Canada [73] Assignce: General Crane lndustries Limited, Ontario, Canada 22 Filed: Nov. 2,1972

21 Appl. No.: 303,042

[30] Foreign Application Priority Data Nov. 4, 1971 Great Britain 51290/71 [52] US. Cl. 212/46 A, 212/46 B, 212/144 [51] Int. Cl. B66c 23/68 [58] Field of Search.....- 212/59 R, 26, 27, 46 R,

[56] References Cited UNITED STATES PATENTS 3,190,457 6/1965 Linden 212/46 R FOREIGN PATENTS OR APPLICATIONS 1,920,981 11/1969 Germany 212/46 A Primary Examiner-Richard A. Schacher Assistant Examiner-Jeffrey V. Nase Attorney, Agent, or Firm-Jlrady, ()Boyle & 011168 [571 ABSTRACT A mobile tower crane with a tiltable, non-rotatable tower mounted on a mobile platform such as a truck, trailer or semi-trailer vehicle. The mobile platform has raised side members which are effective to reinforce the platform against bending along its length, and also carry raised pivot means for the tower at the rear end of the vehicle, the pivot means co-inciding with the side of the tower which is uppermost when the tower is in the horizontal travelling condition.

9 Claims, 4 Drawing Figures PAIENIEBDEM 5 3856.1 50

sum 1 5 4 The present invention relates to mobile load handling 7 necting the platform means and the tower for moving the tower between these positions, and jib or boom support means mounted at the top of the tower and rotatable about the tower axis, the jib or boom being pivotally mounted on the support means for movement in the vertical plane, and hydraulic cylinder means being provided to cause the movement of the jib in the vertical plane (referred to as luffing movement). it is to be noted that, apart from the use of hydraulic cylinder means for luffing the jib or boom, this crane also differs from more conventional mobile tower cranes in having a tower which isnon-rotatable and which is rigid and self-supporting when erected, and capable of withstanding bending forces in different directions so as to be able to support at its upper end a turntable carrying the jib or boom. In more conventional mobile tower cranes, by contrast, the whole tower is mountedon a turntable carried directly by the vehicle or other mo} bile platform, and the tower and the jib rotate together on the turntable and are braced by cables also connected to the turntable in such manner that the tower itself does not have to withstand substantial bending moments in different directions, but is mainly subject to compression forces. 8

The present invention provides improved mobile platform means, and tower mounting means, for load handling or lifting means and particularly for cranes similar to that of my Canadian Patent No. 842,040 at least in having a non-rotatable tower tiltably mounted on mobile platform means.

ln accordance with the present invention, in a mobile load handling or lifting means comprising mobile platform means, a tower, pivot means mounting the base of the tower on the platform means to allow tilting movement of the tower between a vertical operating position and a substantially horizontal travelling position, and means interconnecting the platform means and the tower for moving the tower between these positions, the platform means includes a generally flat chassis portion and side members extending upwardly from the sides of the chassis portion, along a major part of the chassis length, the side members being effective to reinforce the flat chassis portion against bending along its length in the vertical plane and being spaced apart to accommodate the tower therebetween when the latter is in its travelling position, the pivot means for the tower being carried by the side members at an elevation above the flat chassis portion at least equivalent to a major part of the width of the base of the tower, the tower pivot means being on that side of the tower axis which is uppermost when the tower is in its travelling position.

The upwardly extending side members of the mobile platform means which may be in the form of a vehicle such as a truck, trailer, or semi-trailer, thus performthe dual function of bracing the flat chassis portion of the platform means and also provide a raised mounting for the base of the tower. The side members increase the rigidity of the platform means both against bending along the length thereof and against twisting about a longitudinal axis of the chassis. The use of a raised base mounting for the tower increases the operating height of the tower in relation to the chassis length which is required for accommodating the tower when travelling.

In the preferred arrangement, the tower pivot means is aligned with that side of the tower which is uppermost when the tower is in the travelling position. Preferably, the pivot means carried by the side members are spaced above the flat chassis portion by an amount similar to the width of the tower, so that when the tower is folded into the travelling position the lowermost side thereof lies against the flat chassis portion. Also, in the preferred arrangement the tower pivot means is situated close to the top of the chassis side members, which are thus similar in height to the width of the tower, so that the tower is enclosed between the side members when in the horizontal position.

Preferably, the tower has several telescoping sections, and this increases the advantage of using the raised base mounting as will be explained below.

The invention also provides an improved locking arrangement for the base of the tower, which allows this to be locked into its vertical operating position by remote control, and without any manual insertion of bolts or operation of latches or the like. In accordance with this aspect of the invention, the base of the tower is provided with a pair of locking pins mounted within guide boresin the tower, these guide bores lying generally parallel to but spaced from the pivotal axis of the tower pivot means, and receiving bores for the locking pins are provided in the platform means in positions which are aligned with the locking pins when the tower is in the vertical position, the locking pins being connected to hydraulic cylinder means capable of moving the pins outwardly when the tower is vertical from an inner position in which the pins do not interfere with the tilting movement of the tower, to an outer position in which the locking pins project from their guide bores into the receiving bores in the platform means, thus locking the tower in the vertical position. In a preferred arrangement, each of the locking pins is operated by an individual hydraulic cylinder means aligned with the locking pin.

The invention will further be described by way of example with reference to the accompanying drawings in which:

FIG. 1 shows a side elevation of the complete crane in the operating condition,

FIG. 2 shows a side elevation of the complete crane in the travelling condition,

FIG. 3 shows, in side elevation, an enlarged view of the base mounting arrangement for the tower with the tower in the vertical position, and

FIG. 4 is a cross-sectional view on lines 4-4 of FIG. 3.

Referring to the drawings, FIGS. 1 and 2 illustrate a crane basically similar to that described in my Canadian Patent No. 842,040, but with various modifications to be described herein and also in copending U.S. Pat. appln. Ser. No. 303,041 filed Nov. 2, 1972.

The crane includes mobile platform means in the form of a semi-trailer vehicle, having front and rear Outriggers 11 shown in the operating condition in FIG.

1. The rear Outriggers include horizontal telescopic support members 11a which are pivotal on the vehicle chassis about vertical axes, and both front and rear outriggers have hydraulically operated ground engaging pads 11b. The vehicle has raised side members 12, the rear ends of which provide a raised mounting for pivot means 13 carrying thebase of tower 14. The tower includes four telescoping sections including a base section 14a and upper sections 1412, 14c and 14d, and when these are telescopically collapsed they can be moved between the vertical position and the horizontal travelling position shown in FIG. 2 by hydraulic rams 15 which interconnect the vehicle chassis and the base section of the tower. The semi-trailer vehicle 10, and the nature of the mounting at the base of the tower, with which the present-invention is particularly concerned, will be described in more detail below.

The telescoping sections of the tower are each of lattice type construction. The tower sections are telescopically extendible by means of a multi-section hydraulic cylinder 16 connected between the lowermost and uppermost sections. Full details of this tower, including the cylinder 16, and special means for ensuring rigidity of the tower-sections when either fully extended or fully retracted relative to each other are given in my U.S. Pat. appln. Ser. No. 303,041 filed Nov. 2, 1972.

The top of the tower 14 carries a turntable 20 rotatable by hydraulic slewing means, a cab 21 mounted on the turntable, a tiltable unit'22 mounted on top of the cab'and pivotal about a horizontal pivot 22a for folding the crane under control of a hydraulic cylinder 23, and a boom 24 pivotally mounted on the tiltable unit for movement in the vertical plane (ie., luffing movement). The boom is arranged to be luffed by hydraulic cylinders 25 arranged one at each side of the boom, and the boom is also telescopically extendible under hydraulic control FIG. 1' shows the boom near to its highest position, the boom being movable between this position and an approximately horizontal position by the hydraulic cylinders 25. An engine driven pump 27, and

' tanks 28 for fuel and hydraulic fluid, are also carried by tiltable unit 22. The arrangement at the top of the tower is generally similar to that of the crane described in my U.S. Pat. appln. Ser. No. 144,199 filed May 17, 1971, and this patent application also sets out alternative designsof jib support means which could be used in accordance with this invention.

Referring in 'more detail to the side members 12 of the vehicle 10 and the base mounting for the tower with which the present invention is particularly concerned, it will be seen from FIGS. 1 and 2 that the semi-trailer vehicle 10 has a substantially flat chassis portion or bed indicated at 30 and which occupies at least two-thirds of the length of the trailer portion, and which as will be seen in FIG. 2 supports the underside of the base tower section 14a when the tower is folded into the travelling position. The trailer also includes a slightly raised chassis portion 31 somewhat in the form of a goose-neck, which fits under the cab 21 and boom support structure of the crane when the tower is folded into the travelling position.

The raised side members 12 extend upwardly from the sides of theflat bed 30 and also from the sides of the raised chassis portion 31, the side members thus extending along the full length of the trailer. The main, forward portions of these side members are diagonally braced in such manner that central loads on the associated portion of the chassis bed will produce compressive forces in the braces. The rear portions of the members 12, extending for about one quarter the chassis length, are cross braced. By reason of this diagonal and cross-bracing, the side members 12 are very effective in reinforcing the chassis against bending in the vertical plane along its length, with the result that a trailer of adequate strength can be provided which has much less material than what would be required if the trailer had no raised side members. In fact, the weight of the trailer shown herein is less by about one-third than the weight of a similar trailer having no side members but having the same rigidity provided by a thicker flat chassis.

The side members 12 are spaced apart sufficiently to accommodate the folded tower therebetween, and the The pivot means 13 on-which the'tower is tiltably mounted include bearing means 13 which carry stubshafts extending from the lateral sides of the base tower section 14a, these stub-shafts being aligned with the right hand side of the tower as shown in FIG. 1, this being the side of the tower which is uppermost in the travelling position. The bearing means 13a are carried at the rear ends of the side members 12, and very near to the rear end of the trailer (excluding the Outriggers). The height of the bearing means 13a from the top of the chassis bed 30 is equivalent to the distance between these bearing means and the side of the tower which is lowermost during travelling so that when folded the base tower section is supported on bed 30.

It will be apparent that with this pivoting arrangement, the base of the tower lies very close to the end of the trailer vehicle when the tower is in the horizontal v travelling position, so that the length of the trailer vehicle is utilized to the maximum. In practice, the extra length of tower sections which can be accommodated with a mounting arrangement as described, as compared with a mounting arrangement of the type shown in my Canadian Patent No. 842,040 in which the pivot means for the tower is at the side of the tower which is lowermost during travelling, amounts to an increase in tower section length of about 7 feet. This means that each of the four telescoping sections is 7 feet longer than would be possible with the arrangement shown in Canadian Patent No. 842,040, so that the total gain in height for the tower in this particular crane is about 28 feet.

FIGS. 3 and 4 also show particular details. of the instead of double acting rams. The base of the base tower section and the side members 12, are provided with co-operating locking means for holding the tower in the vertical position, which will be described more fully with reference to FIG. 4. The base of the tower is provided with a pair of locking pins 40 slidable with guide bores formed in the side plates 41 at the base of the tower near to the front side of the tower (the left hand side of FIG. 1) and in associated plates 42 spaced inwardly from plates 41, the bores thus being spaced by an amount similar to the tower width from the pivotal axis 13. The guide bores are also co-axial with each other, and are parallel to the pivotal axis of the tower on the pivot means 13. The side members 12 are provided with receiving bores 38a for the locking pins 40 in positions which are aligned with the locking pins when the tower is in the vertical operating position, these receiving bores 38a being located in extensions of the side members 12 provided by the upper ends of plates 38 welded inside the side members. The inner end of each of the locking pins is provided with a clevis mount which is pivotally connected to the end of a piston rod extending from a hydraulic cylinder 43, the inner end of the hydraulic cylinder being pivotally mounted on a mounting 44 welded to the base plate 45 of the base tower section. Thus, an individual hydraulic cylinder is provided for each of the locking pins, each hydraulic cylinder being capable of moving the attached locking pin from an inner position in which the outer end of the locking pin is substantially flush with the lateral side of the tower so that it does not interfere with tilting movement of the tower, to an outer position in which the locking pin projects from its guide bore into the receiving bore 38a carried by-the side member 12 of the trailer. The guide boresgive firm support for the locking pins over a large part of their length so that the projecting portions in the receiving bores 38a are capable of withstanding substantial lateral forces, and the pair of locking pins serves to hold the tower firmly in the vertical position when extended into receiving 1 bores 38a. The cylinders 43 are operated by remote control, so that no manual operation is required in locking the tower into its vertical operating position.

In order to ensure proper vertical positioning of the tower prior. to operating the cylinders 43 to move the pins into the locking position, interengaging machined surfaces are provided on the upper sides of plates 50 welded to' the sides of the base tower section and on the lower surface of plates 52 welded to the plates 38 in the region of bores 38a. Both of these plates have engaging portions which are horizontal and which abut together when the tower has been raised in the vertical position by the hydraulic cylinder 15. Additionally, both plates have sloped, interlocking engaging portions particularly shown at 54 in FIG. 4, which act to hold theside members 12 against outward bending movement particularly on outwards movement of pins 40. Also, the outer ends of the locking pins are preferably tapered so that they can move readily into the receivingbores.

In operation, the crane may be driven to a suitable sitein the condition shown in FIG. 2, and the outriggers are then extended and put into operation to support the trailer vehicle. The tower is then raised to its vertical position (while still telescopically collapsed) by operation of the hydraulic rams 15. Once in this vertical position, the hydraulic cylinders 43 are pressurized in such manner as to cause the locking pins 40 to move outwardly into the receiving bores 38a, the tower then being locked firmly in the vertical position. Simultaneously with raising of the tower by rams 15, the hydraulic cylinder 23 is actuated to move the tiltable unit 22 into the operable position shown in FIG. 1, simultaneous operation of the cylinders 15 and 23 allowing the tiltable unit, and the boom, to remain substantially horizontal during. the whole erection operation. This is quite important, since the tiltable unit carries the fuel and hydraulic fluid tanks 28 which would be spilled if tilted far fromthe horizontal. The tower sections are then telescopically extended to the required height, in the manner particularly described in my US. Pat. appln. Ser. No. 303,041 filed Nov. 2, 1972. The crane operator then climbs the tower and enters the cab 21 at which stage the crane is ready for operation.

Folding of the crane into the travelling position is the reverse of the procedure outlined above.

Alternative arrangements are possible in accordance with this invention; for example the raised mounting for the tower provided by the chassis side members could be central of the vehicle, for example in the position shown in my copending US. Pat. appln. Ser. No. 144,199 filed May 17, 1971. With the configuration shown in this application, the main part of the side members would be below the height of the tower pivot.

Thepresent invention is also applicable to mobile towers for other purposes then cranes, for example for fire-fighting and rescue equipment. Such load handling or lifting means may include a fire ladder mounted on the top of the tower, being longitudinally extendible and capable of luffing movement in the vertical plane in the same manner as a crane boom.

1 claim: l m

1. Mobile load handling or lifting means comprising mobile platform means including a vehicle such as a truck, trailer or semi-trailer, a tower, pivot means mounting the base of the towerv on the platform means to allow tilting movement of the tower between a vertical operating position and a substantially horizontal travelling position, and means interconnecting the platform means and the tower for moving the tower be- I tween these positions, said vehicle having a substantially flat chassis bed portion and side members connected to and extending upwardly from the sides of the vehicle flatbed portion along a major part of the length of the flat bed portion, said side members being spaced apart to accommodate the tower therebetween when the latter is in its foldedtravelling position and wherein the tower is supportedby said flatbed portion, the side members including bracing means for reinforcing the flat bed portion against bending along its length in the vertical plane due to the'weight of the tower thereon in the folded travelling position, the pivot means for the tower being carried by the side members at an eleva-' tion above the flat bed portion at least equivalent to a major part of the width of the base of .the tower, the tower pivot means being disposed above the longitudinal axis of the tower when the tower is in its travelling position.

2. Mobile load handling or lifting means according to claim 1, wherein the pivot means is aligned with that side of the tower which is uppermost when the tower is in the travelling position, and the pivot means is also spaced above the flat bed portion by an amount similar to the width of the tower.

3. Mobile load handling or lifting means according to claim 2, wherein the tower pivot means is situated at the top of the flat bed side members.

4. Mobile load handling or lifting means according to claim 1, wherein the base of the tower is provided with a pair of locking pins mounted within guide bores in the tower, these guide bores lying generally parallel to but spaced from the pivotal axis of the tower pivot means,

and receiving bores for the locking pins are provided in the side members in positions which are aligned with the locking pins when the tower is in the vertical position, the locking pins being connected to hydraulic cylinder means capable of moving the pins outwardly when the tower is .vertical from an inner position in which the pins do not interfere with the tilting movement of the tower, to an outer position in which the locking pins project from their guide bores into the receiving bores in the side members, thus locking the tower in the vertical position.

5. Mobile load handling or lifting means according to claim 1, wherein said side members are of lattice structure. v

6. Mobile load handling or lifting means according to claim 1, wherein locking means are operatively connected between the base of the tower and the side members for locking the tower in the vertical position.

7. Mobile load handling or lifting means according to claim 6, wherein said locking means comprises a pair of oppositely extending pins slidably mounted on the base of the tower, and a pair of bores provided in the side members, each bore adapted to receive a respective pin when the tower is disposed in the vertical position.

8. Mobile load handling or lifting means according to claim 6, wherein said locking means are disposed at the top of the flat bed side members when the tower is in the vertical position.

9. Mobile load handling or lifting means according to claim 8, wherein said locking means and pivot means are disposed in substantially the same horizontal plane when the tower is in the vertical position. 

1. Mobile load handling or lifting means comprising mobile platform means including a vehicle such as a truck, trailer or semi-trailer, a tower, pivot means mounting the base of the tower on the platform means to allow tilting movement of the tower between a vertical operating position and a substantially horizontal travelling position, and means interconnecting the platform means and the tower for moving the tower between these positions, said vehicle having a substantially flat chassis bed portion and side members connected to and extending upwardly from the sides of the vehicle flat bed portion along a major part of the length of the flat bed portion, said side members being spaced apart to accommodate the tower therebetween when the latter is in its folded travelling position and wherein the tower is supported by said flat bed portion, the side members including bracing means for reinforcing the flat bed portion against bending along its length in the vertical plane due to the weight of the tower thereon in the folded travelling position, the pivot means for the tower being carried by the side members at an elevation above the flat bed portion at least equivalent to a major part of the width of the base of the tower, the tower pivot means being disposed above the longitudinal axis of the tower when the tower is in its travelling position.
 2. Mobile load handling or lifting means according to claim 1, wherein the pivot means is aligned with that side of the tower which is uppermost when the tower is in the travelling position, and the pivot means is also spaced above the flat bed portion by an amount similar to the width of the tower.
 3. Mobile load handling or lifting means according to claim 2, wherein the tower pivot means is situated at the top of the flat bed side members.
 4. Mobile load handling or lifting means according to claim 1, wherein the base of the tower is provided with a pair of locking pins mounted within guide bores in the tower, these guide bores lying generally parallel to but spaced from the pivotal axis of the tower pivot means, and receiving bores for the locking pins are provided in the side members in positions which are aligned with the locking pins when the tower is in the vertical position, the locking pins being connected to hydraulic cylinder means capable of moving the pins outwardly when the tower is vertical from an inner position in which the pins do not interfere with the tilting movement of the tower, to an outer position in which the locking pins project from their guide bores into the receiving bores in the side members, thus locking the tower in the vertical position.
 5. Mobile load handling or lifting means according to claim 1, wherein said side members are of lattice structure.
 6. Mobile load handling or lifting means according to claim 1, wherein locking means are operatively connected between the base of the tower and the side members for locking the tower in the vertical position.
 7. Mobile load handling or lifting means according to claim 6, wherein said locking means comprises a pair of oppositely extending pins slidably mounted on the base of the tower, and a pair of bores provided in the side members, each bore adapted to receive a respective pin when the tower is disposed in the vertical position.
 8. Mobile load handling or lifting means according to claim 6, wherein said locking meaNs are disposed at the top of the flat bed side members when the tower is in the vertical position.
 9. Mobile load handling or lifting means according to claim 8, wherein said locking means and pivot means are disposed in substantially the same horizontal plane when the tower is in the vertical position. 